The AI offers advantages like a little better velocity potential and possibly longer case life with a little less case stretching, and therefore maybe less case trimming. You can fire standard .280 ammo in it also, but of course you're better off with brass already formed to AI. Factory AI ammo is available but not ubiquitous. Then again, neither is standard .280 ammo.
If you're a handloader, the AI has a lot going for it.
God I am hating caliber threads more and more